Serverside Asynchronous Updates

Hi,
I need to show some charts on my page. The question is: how to perform it execution in asynch way (with refresh data too)?

I look the https://vaadin.com/docs/v10/flow/advanced/tutorial-push-access.html page but I don’t understand how to implement it as I have 4 charts.
Can somebody help me?

The Thread approach is good looking performance aspect? Or is possible to implement a client approach using polymer?
What is the best way to implement it?

Thanks

In the bottom of this documentation page there is a full example

https://vaadin.com/docs/v10/flow/advanced/tutorial-push-access.html

Push is better approach, since polling UI would generate much more traffic towards the server than pushy UI, so pushy UI almost certainly can serve more users. There is no built in polling in Flow like Vaadin 8 had.

Thanks,
I tried to use the example as described in the link but I have some concerns:

Is the best approach use Threads? This means that if I have 10.000 users connected to tha application I need to start 10.000 threads (server side).

especially if the data to show must be updated continuously